1. Field of the Invention
The present invention relates to an upright microscope.
2. Description of the Related Art
FIG. 11 is a side elevation presenting a sectional view of a portion of an upright microscope in the prior art. This upright microscope 101 comprises a base unit 110, a stand unit 120 and a focusing vertical motion mechanism 140. The base unit 110 is formed in an inverted U shape. The bottom of the base unit 110 is closed off by a base plate 110a. A light source lamp 113 is provided inside a space S formed by the base plate 110a. The light source lamp 113 is set on the optical axis of an objective lens 121.
The light source lamp 113 is mounted at a lamp socket 112 supported by a socket retaining plate 111. The socket retaining plate 111 is secured to an access hatch 115 constituting a portion of the base plate 110a with a screw (not shown) or the like. One end of the access hatch 115 is rotatably supported by the base plate 110a via a pin 116, and its other end is secured to the base unit 110 with a screw 117. A condenser lens unit 130 provided at an upper surface 110d of the base unit 110 is set on the optical axis of the objective lens 121.
The stand unit 120 is located at the end of the base unit 110 and is provided with focusing knobs 153 for driving the focusing vertical motion mechanism 140. The focusing vertical motion mechanism 140 is supported by a linear guide mechanism such as a cross roller race, a ball race or a dovetail groove (not shown) along the stand unit 120 in such a manner that it can move vertically, and is provided with a stage 166. The focusing vertical motion mechanism 140 is connected to the focusing knobs 153 via a rack and pinion (not shown) and the stage 166 is caused to move vertically by rotating the focusing knobs 153.
When replacing the light source lamp 113 when it burned out in this upright microscope 101, it is necessary to pull out the lamp socket 112 (the lamp 113) from the space S by (1) laying down the upright microscope 101 rearward or sideways, (2) removing the screw 117 retaining the access hatch 115 and (3) opening the access hatch 115.
Thus, the replacement of the light source lamp 113 is a complicated process and furthermore, there is a risk of striking the stage 166, the focusing knobs 153, a lens barrel 124, the power cord or the like by mistake against the desk when the upright microscope 101 is laid down, causing them damage.
In addition, since the focusing vertical motion mechanism 140, the focusing knobs 153, the condenser lens unit 130, the lamp socket 112 and the like must be mounted at the stand unit 120 and the base unit 110 in a specific order, the assemblability (productivity) is poor.
Moreover, since the focusing vertical motion mechanism 140 and the focusing knobs 153 are provided at the stand unit 120, the focusing knobs 153 are set at a high position distanced from the desk surface further rearward relative to the stage handle (not shown). As a result, it is difficult for the user to operate the focusing knobs 153 and the stage handle while keeping his hands on the desk, and therefore the operability is poor.